This invention is related to the coupler key mounting for an "E" type coupler for a railway car. More particularly, the invention is related to the coupler key mount in a railway end-of-car cushioning unit for mounting an "E" type coupler.
The best known prior art is shown on FIGS. 1 and 2 of the drawings and labeled as "Prior Art". In FIGS. 1 and 2, a railway car center sill is indicated partially at 10 and receives in its open end an end-of-car cushioning unit generally indicated at 12. Cushioning unit 12 has an open ended housing 18 secured at one end to cyclinder 20 and receiving within its other open end a shank 21 of an E-type coupler 14. Coupler key 16 is received within apertures or slots 22 and 23 in opposed sides of center sill 10. Draft lugs 24 and 26 on opposed sides of housing 18 are adapted to abut fixed draft lugs 28 and 30 secured to opposed sides of center sill 10.
Cushioning unit 12 is installed within center sill 10 with draft lugs 24 and 26 in abutting relation to draft lugs 28 and 30. Then with coupler shank 21 within housing 18, key 16 is positioned within an aperture 32 through one side of sill 10 and thence through slots 22 and 23 and a suitable aligned slot in coupler shank 21. After coupler key 16 is positioned, a retainer 34 is bolted to center sill 10 and secured to sill stiffener 36. In this position, coupler key 16 can move laterally within housing 18 and shank 21 since it is not rigidly fastened. Key 16 does, however, move longitudinally with housing 18 and shank 21 relative to center sill 10 upon the exertion of impact forces against coupler 14.
The main deficiency in the prior art as illustrated in FIGS. 1 and 2 is that coupler key 16 sometimes is moved laterally from side to side and coupler key 16 can be dislodged from its normal position to a position where one end of the key substantially extends from one side of open ended housing 18. This particular position of coupler key 16 can and has in practice caused open ended housing 18 to be jammed against one side of center sill 10 with the key extending from its opposite side. This jamming prevents side to side movement of open ended housing 18 and additionally prevents its retraction into center sill 10 during buff loading. In order to prevent this jamming, a guide block 38 is welded to retainer 34 and another guide block 39 is welded to the opposed side of the center sill as shown. These blocks 38 and 39 will prevent coupler key 16 from being substantially displaced from open ended housing 18 when the cushioning unit is in the fully extended position. Another disadvantage to this type of mounting structure is that the two pairs of front draft lugs must be welded in the center sill during the car construction and positioned to within close tolerances for the cushioning unit to operate properly. In the normal construction of a railway car, the center sill is installed long before the cushioning unit 12 has to be installed. When the cushioning unit is to be installed the front draft lugs must be welded in place in their proper position inside the sill before the cushioning unit can be installed. This operation is time consuming and tedious in order to position the lugs so that they have the proper spacing relative to the end of the sill and so they have the proper spacing to allow the coupler key 16 to move forward and rearward. It is to be understood that the structure shown and described herein as prior art is not the only structure known prior to the herein disclosed invention. However, it is believed to be the most pertinent prior art.